The speaker was one of the principals for this company: NW Digital Radio and they are bringing technology from the commercial side of two-way communications over to the amateur radio side. With radio, there is only so much bandwidth available and each simultaneous conversation takes up a specific chunk of it. Too many people trying to communicate and the last people going on the air wind up being unable to talk - no more bandwidth.
Commercial radios (Police, Fire, Business, Civil Service, &c) have started to use digital techniques to compress speech and allow it to be transmitted using much less bandwidth. An added benefit is that the quality of speech is very good without the background hissing and signal fading common in the analog world. Commercial radio users tend to have money to spend so their needs drive the development of the technology.
This also allows for the flawless transmission of data - error correction is inserted into the transmission so when someone reports a attack from a Marmota marmota, they will know it is one of these that needs to be dealt with:
The upshot is that they have this $90 board (PDF file) that plugs into a $40 Raspberry-Pi computer and does end-to-end digital conversion over normal ham radio channels.
They also offer this $120 vocoder (PDF file) for doing voice transmissions over a digital connection (the vocoding technology is patented and licensed by another company hence the higher price).
Very fun time to be alive and doing radio!
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